Authorities have arrested at least one person after a vehicle struck pedestrians and caused "a number of casualties" near a London mosque early Monday morning, London Metropolitan Police said in a statement.

The crash took place around 8 p.m. ET Sunday in Finsbury Park -- a neighborhood where many immigrants live, CNN reported.

Some of the victims were worshippers leaving a local mosque, the Muslim Council of Britain said. A service celebrating the Muslim holy month of Ramadan had recently ended, and attendees were emptying out into the street.

The Finsbury Park mosque was associated with extremist ideology following the 9/11 attacks in the United States before closing down and undergoing reorganization, The Associated Press reported. It has not been associated with radical views for more than a decade.

The intersection where the collision occurred has since been closed, officials said. Police referred to the crash as a "major incident."

Authorities have yet to publicize a cause for the collision. However, the Britain terrorist alert has been set to "severe" -- meaning an attack is highly likely, The Associated Press reported.

Weeks ago, a van rammed into pedestrians on London Bridge, triggering a wave of vehicle and knife attacks that left eight dead and many injured. The three Muslim extremists found guilty of planning the attack were later killed by police.